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MOT FAIL - High Lambda Honda Jazz
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Tom Burton
Feb 19, 2012, 5:40:42 PM2/19/12
to
Hi Again
I mangaged the Rear Pads and Disks on the Honda Jazz 1.4 04 plate as
mentioned in an earlier thread and took the car for an MOT.
Passed on everything except the Emissions which failed on High Lambda
with a reading of
1st Test 1.072
2nd Test 1.051
All other gasses were well within spec and easy passes.
Whilst the car was up on the ramp we noticed two VERY small exhaust
blows, one from the mid section and one from the coupling of back box &
mid section. These were very hard to detect bearly audiable and couldnt
really be felt "blowing" however the dectector spray showed them up.
I have replaced mid and rear sections - mid section twice as the
replacement was blowing worse than the original!
My scanner shows 02 sensor 1 with a voltage of around 0.6v and 02 sensor
2 with a voltage of about 0.45v.
The car was presented for MOT hot and after an italian tune up, it was
also serviced... Plugs, Oils Filters etc in the days prior to the MOT.
My questions are do you think that the exhaust blow could cause the high
Lambda reading?
If not the exhaust what would be the next port of call for Lambda issues
(im much happier with disels!)
TIA
Tom
Mrcheerful
Feb 20, 2012, 4:00:36 AM2/20/12
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Dave Plowman (News)
Feb 20, 2012, 5:58:40 AM2/20/12
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In article <KTe0r.81305$ZT6....@newsfe23.ams2>,
A lambda reading above 1 shows it's running weak. 1.07 equates to an AFR
of 15.7:1 I'd expect other gasses to show up 'wrong' too - can you give
all the readings?
--
*Suicidal twin kills sister by mistake.
Dave Plowman da...@davenoise.co.uk London SW
To e-mail, change noise into sound.
Tom Burton <thomas...@RatherWarmMail.com> wrote:
> My questions are do you think that the exhaust blow could cause the high
> Lambda reading?
Only if the leaks are beyond the sensors.
> My questions are do you think that the exhaust blow could cause the high
> Lambda reading?
A lambda reading above 1 shows it's running weak. 1.07 equates to an AFR
of 15.7:1 I'd expect other gasses to show up 'wrong' too - can you give
all the readings?
--
*Suicidal twin kills sister by mistake.
Dave Plowman da...@davenoise.co.uk London SW
To e-mail, change noise into sound.
Tom Burton
Feb 20, 2012, 7:17:54 AM2/20/12
to
On 20/02/2012 10:58, Dave Plowman (News) wrote:
> In article<KTe0r.81305$ZT6....@newsfe23.ams2>,
> Tom Burton<thomas...@RatherWarmMail.com> wrote:
>> My questions are do you think that the exhaust blow could cause the high
>> Lambda reading?
>
> Only if the leaks are beyond the sensors.
>
> A lambda reading above 1 shows it's running weak. 1.07 equates to an AFR
> of 15.7:1 I'd expect other gasses to show up 'wrong' too - can you give
> all the readings?
>
Sorry I should have been clearer, both sensors are on the front section
> In article<KTe0r.81305$ZT6....@newsfe23.ams2>,
> Tom Burton<thomas...@RatherWarmMail.com> wrote:
>> My questions are do you think that the exhaust blow could cause the high
>> Lambda reading?
>
> Only if the leaks are beyond the sensors.
>
> A lambda reading above 1 shows it's running weak. 1.07 equates to an AFR
> of 15.7:1 I'd expect other gasses to show up 'wrong' too - can you give
> all the readings?
>
of exhaust, just before and just after the cat.
Full Gasses are
Fast Idle Test 1
CO - 0.11% (Limit =<0.30%)
HC - 35ppm (Limit =<200ppm)
Lamda - 1.072 (Limit 0.97 - 1.03)
Fast Idle Test 2
CO - 0.06% (Limit =<0.30%)
HC - 5ppm (Limit =<200ppm)
Lamda - 1.051 (Limit 0.97 - 1.03)
Nat Idle
CO - 0.04% (Limit =<0.50%)
Many Thanks
Tom Burton
Feb 20, 2012, 7:22:10 AM2/20/12
to
On 20/02/2012 09:00, Mrcheerful wrote:
> Tom Burton wrote:
>> Hi Again
<snip>
> Tom Burton wrote:
>> Hi Again
>>
>> Tom
>
> yes, an exhaust blow can certainly cause the lambda fail.
>
>
pipe it would suck in clean air behind each wave this leading to dodgy
readings?
Tom
Tim..
Feb 20, 2012, 7:24:42 AM2/20/12
to
"Tom Burton" <thomas...@RatherWarmMail.com> wrote in message
news:KTe0r.81305$ZT6....@newsfe23.ams2...
>
> Hi Again
>
> I mangaged the Rear Pads and Disks on the Honda Jazz 1.4 04 plate as
> mentioned in an earlier thread and took the car for an MOT.
>
> Passed on everything except the Emissions which failed on High Lambda with
> a reading of
>
> 1st Test 1.072
> 2nd Test 1.051
>
> All other gasses were well within spec and easy passes.
>
> Whilst the car was up on the ramp we noticed two VERY small exhaust blows,
> one from the mid section and one from the coupling of back box & mid
> section. These were very hard to detect bearly audiable and couldnt really
> be felt "blowing" however the dectector spray showed them up.
YES - seal the exhaust, lambda over 1 is weak from the extra air. You'll
> Hi Again
>
> I mangaged the Rear Pads and Disks on the Honda Jazz 1.4 04 plate as
> mentioned in an earlier thread and took the car for an MOT.
>
> Passed on everything except the Emissions which failed on High Lambda with
> a reading of
>
> 1st Test 1.072
> 2nd Test 1.051
>
> All other gasses were well within spec and easy passes.
>
> Whilst the car was up on the ramp we noticed two VERY small exhaust blows,
> one from the mid section and one from the coupling of back box & mid
> section. These were very hard to detect bearly audiable and couldnt really
> be felt "blowing" however the dectector spray showed them up.
then pass the test. Seen this 1000's of times before...
Tim.
Mrcheerful
Feb 20, 2012, 7:30:19 AM2/20/12
to
only blocking an exhaust blow, literally put in the gungum and watch the
readings correct themselves.
Dave Plowman (News)
Feb 20, 2012, 9:39:07 AM2/20/12
to
In article <44r0r.177705$WX2.1...@newsfe28.ams2>,
I have a wideband O2 sensor on the old Rover. I recently had a bad leak
where the rear box bolts to the pipe - just came loose. Didn't make a
scrap of difference to the idle reading.
--
*It was recently discovered that research causes cancer in rats*
Mrcheerful <g.odon...@yahoo.co.uk> wrote:
> > Is that becuase as the "presure wave" of exhaust gass moves down the
> > pipe it would suck in clean air behind each wave this leading to dodgy
> > readings?
> > Is that becuase as the "presure wave" of exhaust gass moves down the
> > pipe it would suck in clean air behind each wave this leading to dodgy
> > readings?
> I don't know the mechanism, but I have definitely seen lambda fails
> cured by only blocking an exhaust blow, literally put in the gungum and
> watch the readings correct themselves.
Interesting. And this is leaks well downstream of the sensor(s)?
> cured by only blocking an exhaust blow, literally put in the gungum and
> watch the readings correct themselves.
I have a wideband O2 sensor on the old Rover. I recently had a bad leak
where the rear box bolts to the pipe - just came loose. Didn't make a
scrap of difference to the idle reading.
--
*It was recently discovered that research causes cancer in rats*
Dave Plowman (News)
Feb 20, 2012, 9:49:46 AM2/20/12
to
In article <RRq0r.103719$nu3....@newsfe15.ams2>,
at temperture will tend to alter the HC readings - without, they would
likely be high with a weak mixture.
> Fast Idle Test 2
> CO - 0.06% (Limit =<0.30%)
> HC - 5ppm (Limit =<200ppm)
> Lamda - 1.051 (Limit 0.97 - 1.03)
> Nat Idle
> CO - 0.04% (Limit =<0.50%)
Obviously fix the leaks with gunge as the cheapest option. I'll be
interested to know if it sorts things.
--
* What do they call a coffee break at the Lipton Tea Company? *
Tom Burton <thomas...@RatherWarmMail.com> wrote:
> On 20/02/2012 10:58, Dave Plowman (News) wrote:
> > In article<KTe0r.81305$ZT6....@newsfe23.ams2>,
> > Tom Burton<thomas...@RatherWarmMail.com> wrote:
> >> My questions are do you think that the exhaust blow could cause the
> >> high Lambda reading?
> >
> > Only if the leaks are beyond the sensors.
That should have read before the sensors. ;-)
> On 20/02/2012 10:58, Dave Plowman (News) wrote:
> > In article<KTe0r.81305$ZT6....@newsfe23.ams2>,
> > Tom Burton<thomas...@RatherWarmMail.com> wrote:
> >> My questions are do you think that the exhaust blow could cause the
> >> high Lambda reading?
> >
> > Only if the leaks are beyond the sensors.
> >
> > A lambda reading above 1 shows it's running weak. 1.07 equates to an
> > AFR of 15.7:1 I'd expect other gasses to show up 'wrong' too - can you
> > give all the readings?
> >
> Sorry I should have been clearer, both sensors are on the front section
> of exhaust, just before and just after the cat.
> Full Gasses are
> Fast Idle Test 1
> CO - 0.11% (Limit =<0.30%)
> HC - 35ppm (Limit =<200ppm)
> Lamda - 1.072 (Limit 0.97 - 1.03)
Low CO in combination with high lambda confirms a weak mixture. The cat if
> > A lambda reading above 1 shows it's running weak. 1.07 equates to an
> > AFR of 15.7:1 I'd expect other gasses to show up 'wrong' too - can you
> > give all the readings?
> >
> Sorry I should have been clearer, both sensors are on the front section
> of exhaust, just before and just after the cat.
> Full Gasses are
> Fast Idle Test 1
> CO - 0.11% (Limit =<0.30%)
> HC - 35ppm (Limit =<200ppm)
> Lamda - 1.072 (Limit 0.97 - 1.03)
at temperture will tend to alter the HC readings - without, they would
likely be high with a weak mixture.
> Fast Idle Test 2
> CO - 0.06% (Limit =<0.30%)
> HC - 5ppm (Limit =<200ppm)
> Lamda - 1.051 (Limit 0.97 - 1.03)
> Nat Idle
> CO - 0.04% (Limit =<0.50%)
interested to know if it sorts things.
--
* What do they call a coffee break at the Lipton Tea Company? *
Tom Burton
Feb 20, 2012, 10:00:21 AM2/20/12
to
>
> Obviously fix the leaks with gunge as the cheapest option. I'll be
> interested to know if it sorts things.
>
Hopefully going for a re-test tomorrow so I'll let you know!
Tom
Mrcheerful
Feb 20, 2012, 10:51:39 AM2/20/12
to
Dave Plowman (News) wrote:
> In article <44r0r.177705$WX2.1...@newsfe28.ams2>,
> Mrcheerful <g.odon...@yahoo.co.uk> wrote:
>>> Is that becuase as the "presure wave" of exhaust gass moves down the
>>> pipe it would suck in clean air behind each wave this leading to
>>> dodgy readings?
>
>
>> I don't know the mechanism, but I have definitely seen lambda fails
>> cured by only blocking an exhaust blow, literally put in the gungum
>> and watch the readings correct themselves.
>
> Interesting. And this is leaks well downstream of the sensor(s)?
>
> I have a wideband O2 sensor on the old Rover. I recently had a bad
> leak where the rear box bolts to the pipe - just came loose. Didn't
> make a scrap of difference to the idle reading.
yep, after the sensors, I assume it must be to do with backpressure, but it
> In article <44r0r.177705$WX2.1...@newsfe28.ams2>,
> Mrcheerful <g.odon...@yahoo.co.uk> wrote:
>>> Is that becuase as the "presure wave" of exhaust gass moves down the
>>> pipe it would suck in clean air behind each wave this leading to
>>> dodgy readings?
>
>
>> I don't know the mechanism, but I have definitely seen lambda fails
>> cured by only blocking an exhaust blow, literally put in the gungum
>> and watch the readings correct themselves.
>
> Interesting. And this is leaks well downstream of the sensor(s)?
>
> I have a wideband O2 sensor on the old Rover. I recently had a bad
> leak where the rear box bolts to the pipe - just came loose. Didn't
> make a scrap of difference to the idle reading.
works, last one was a 1.8 vectra with a little leak just at the exit of the
centre exhaust box.
Chris K
Feb 20, 2012, 2:29:09 PM2/20/12
to
which is engine exhaust "contaminated with" air (which is 20% O2) drawn
in through the exhaust holes. Not really a fail, more an artefact of
the measurement technique.
Really, with modern closed loop systems, high O2 measured at the
tailpipe isn't really a pollution problem if all other readings are OK.
If the ECU is not declaring an O2 sensor problem, is must be OK.
Isn't is about time the MoT included taking readings from the OBD-2 port
into account?
Chris K
Duncan Wood
Feb 20, 2012, 4:07:42 PM2/20/12
to
someone to fix a leaky exhaust.
Chris K
Feb 20, 2012, 5:29:15 PM2/20/12
to
advisory rather than declaring a pollution fault.
CK
Mrcheerful
Feb 21, 2012, 2:50:47 AM2/21/12
to
testing can make almost any car fail.
Tim..
Feb 21, 2012, 5:37:10 AM2/21/12
to
"Tom Burton" <thomas...@RatherWarmMail.com> wrote in message
Tim.
Tom Burton
Feb 21, 2012, 11:57:17 AM2/21/12
to
Results of the ReTtest are in,
Emma is delighted to report that "Jerry the Jazz" (Do men ever name
cars?) has passed the MOT Exam.
With nothing else changed other than the Middle and Tail Sections of the
exhaust (Car was also presented warm rather than hot)
Fast Idle Test:
CO - 0.03% - PASS (Limit =< 0.20% )
HC - 33PPM - PASS (Limit =< 200ppm )
Lambda - 0.997 - Pass (Limit 0.97 - 1.03)
Natural Idle
CO - 0.02% - Pass (Limit =< 0.30% )
Incidentally Last Years figures are identical with the exeption of the
HC which last year was 0 ppm.
Last year the car had not been serviced for at least 80'000miles had an
air filter that was covered in something that looked like treacle and
the plugs had a gap you could drive a bus through! The engine contained
about a mug full of oil that had the consistancey of snot when warm!
Oh and the brakes bore more resemblance to those used on trains, being
metal on metal!
Thanks for all your help
Tim..
Feb 22, 2012, 4:06:20 AM2/22/12
to
"Tom Burton" <thomas...@RatherWarmMail.com> wrote in message
to the engine being worn out !!!
Tim.
Tom Burton
Feb 22, 2012, 6:26:26 PM2/22/12
to
>>
>> Incidentally Last Years figures are identical with the exeption of the
>> HC which last year was 0 ppm.
>> Last year the car had not been serviced for at least 80'000miles had
>> an air filter that was covered in something that looked like treacle
>> and the plugs had a gap you could drive a bus through! The engine
>> contained about a mug full of oil that had the consistancey of snot
>> when warm!
>
> So you'll probably be back at next year's MOT time with failed gas test
> due to the engine being worn out !!!
>
> Tim.
>
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